In the field of medical treatment, when inserting a surgical tool into the body, a tubular surgical tool insertion aid is used which aids insertion of the surgical tool.
Conventionally, as a surgical tool insertion aid, a multi-lumen tube endoscope is known in which a plurality of flexible tubes are integrally fixed as inner tubes that form an image guide conduit, a light guide conduit, a treatment channel conduit, an air/water feeding channel conduit or the like.
According to the aforementioned surgical tool insertion aid, because the diameter and shape of a conduit can be ensured by means of a flexible tube, the insertability of a surgical tool can be improved at a time of use (for example, see Patent Literature 1).